On the heels of last week’s successful initial public offering that raised hundreds of million of dollars from investors, pharmaceutical services giant Quintiles disclosed Tuesday in a securities filing that it plans to cut about 400 jobs worldwide this year. The 400 jobs amount to about 1.5 percent of the Durham-based company’s 27,000 employees around the globe. Quintiles said in a statement that “the size and composition of our workforce routinely fluctuates based on project and business needs. Also, it is equally important to note that Quintiles’ workforce has grown over the last five years.”Spokesman Phil Bridges declined to comment on the impact of the job cuts on the company’s more-than-2,000 Triangle workers. Bridges also noted the company has 900 open positions worldwide that it is seeking to fill.